I'm told this is the peak of the franchise and I'm inclined to believe that. The action is fast and fun, the levels aren't horribly repetitive, and you have a good variety of weapons at your disposal to screw around with. About the only things I disliked were that some of the guns were undertuned and they probably could handled the Cortana acid trips a little better. Definitely give this one a look if you've ever wanted to check out Halo.